A Chelsea spokesman came into the press room at the otherwise empty stadium and said, with a solemnity that alerted everyone to its seriousness, that he had a statement to make.

The club, he said, had made a complaint to the match delegate that referee Mark Clattenburg had used “inappropriate language” to two Chelsea players during the match.

“The Premier League match delegate will pass the complaint to the Football Association,” he said.

Soon afterwards, to a general reaction of astonishment, it became apparent that Chelsea were alleging that Clattenburg had verbally abused their midfielder Jon Obi Mikel.

The second allegation is believed to relate to inappropriate language used against one of Chelsea’s Spanish players.

And so, just as English football appeared to be on the verge of ridding itself of some of the rancour that has poisoned it, it has been plunged into a fresh crisis.

This is potentially more serious than the others, even though the Terry-Ferdinand case cost Fabio Capello the England manager’s job and Terry the England captaincy.

This involves serious allegations made against a senior official, a man in a position of authority.

This involves one of England’s best-known referees and allegations that he verbally abused a man who plays for the Champions of Europe.

It also follows hard on the heels of the Terry-Ferdinand case and the passions inflamed by the Luis Suarez-Patrice Evra case which preceded it.

Last night’s allegations also have the potential to set Chelsea against the governing body once more.

It was, in short, the last thing the English game needed as it began to try to pick up the pieces after the previous controversies. It was not known last night what Clattenburg’s response to the allegations will be.

But the claims also raise the prospect of bringing the referees’ official body, the Professional Game Match Officials Board, into conflict with the players.

It raises fundamental questions about how referees ‘manage’ matches and whether they have become too familiar with players.

And it raises questions about how much the already strained relationship between referees and players will be damaged by these allegations.